Stamp-mill



(No Model.) 2 Sheets-Sheet 1.

J. M. MOFARLAND. I

STAMP MILL.

No. 467,187. Patented Jan. 19, 1892-.

(No Model.) 2 Sheets-Sheet 2.

' J. M. MOPARLAND.

STAMP MILL.

' Patented Jan. 19 1892.

who 0 'mfm fimlwa UNITED STATES PATENT OFFICE.

JAMES M. MCFARLAND, OF VIRGINIA CITY, NEVADA.

STAMP-MILL.

SFEGIFICATION forming part of Letters Patent No. 467,187, dated January19, 1892.

Application filed May 11, 1891. Serial No. 392.370. (No model.)

To all whom it may concern:

Be it known that I, JAMES M. MCFARLAND, of Virginia City, in the countyof Storey and State of Nevada, have invented certain new and usefulImprovements in Stamp-Mills; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

My invention relates to an improvement in stamp-mills.

The stamp mill or battery as actually used is constructed about asfollows: A solid foundation, called the mortar-block, is constructed ofheavy timbers set up on ends and bolted together, the bottom endsresting on masonry or other firm foundation. The foundation-timbers forthe frame-Work of the mill are preferably independent of themortarblock, so that the former will not be affected by the constant andcontinuous jar to which the latter are subjected. The posts which carrythe cam-shaft and guides are secured to the foundation-timbers, theinside distance between the posts being equal to the length of themortar. The upper ends of the posts are held apart and supported nearthe top by a cross-beam, and are further braced and supported by asecond cross-beam placed so as to come slightly above the top of themortar, thesetwo cross-beams carrying the guides for holding the stampsin vertical position. The mortar, which is located between the posts onthe mortar-block, is a heavy cast-iron box, extra heavy at the bottom tosuccessfully resist the blows of the stamps. with sides extending upthree or four feet, forming a casing'or housing around the lower ends ofthe stamps. In one side of the housing is an opening for the screen,through which the pulp or sand is discharged, and in the other side is afeedway. The mortar having been bolted to the mortar-block and the diesplaced therein, the apparatus is readyfor the reception of the stamps,each of which ordinarily consists of a stem, a head on lower end ofstem, a shoe in the lower end of the head, and the tappet. secured onthe stem in a position to be engaged on its under side by its 0am. Thecam-shaft, with the cams thereon, is then placed in position and pipesarranged to conduct water into the mortar, it for wet crushing, and thebattery is complete. lVith a stamp-mill thus constructed the wear on thestem of the stamp and the guides supporting the stem is considerable,and more particularly on the lower guides and the portion of the'stemswhich move in contact with said guides. To prevent this Wear on thestems, the guides are in some instances made of wood, and when the shoesand dies become slight-1y worn and the stamps are dropping on hard rockthe stamps are forced from side to side, and the lower guides being fromfir e to six feet above the dies the leverage against the walls of theguides is so great as to soon enlarge the guideways, so that thefriction of the cams draws the stamps away from the center of the dies.lVhen in this condition, the crushing capacity of the battery isreduced,and the expense of keeping these guides in repair amounts toconsiderable. Again, the stamp-stems frequently break and it is oftennecessary to remove a stamp for repair, when if the guides are made ofwood and the battery contains five stamps it is necessary to remove fromtwelve to sixteen nuts from their bolts and drive the bolts back toallow the front section of the guides to be removed.

My invention relates more particularly to the bearings and stamps, theobject being to so construct the bearings that but comparatively littlewear results, thus causing the stamps to maintain at all times theirapproximately vertical position, the said bearings being so constructedand arranged that any one of the stamps can be easily and quicklyremoved without disturbing the others.

In the accompanying drawings, Figure 1 is a view in elevation of astamp-mill embodying my improvements. Fig. 2 is a view in verticalsection taken transversely of the mortar and through the centers of theupper and lower bearings. Fig. 3 is a view of one of the upper bearingsdetached, showing also the bearing-attaching devices. Fig. 4 is a viewin section of the bearings and thecrossbeam carrying thesame, and Fig. 5is a view of the head-shoe and section of stem adj acent to the shoe.

A represents the mortar-bed carrying mortar B, and C are the sidestandards or supports, suitablybraced and carrying the crossbeam D at ornear their upper ends. The mortar is provided at one side with ascreenopening a and on its opposite side with a feed-opening Z). Themortar is provided with a top plate (Z, secured thereon, the said topplate being provided with a series of cylinders or guides 6. Thesecylinders or lower guides 6, together with the top plate (I, whichcloses the top of the mortar, are cast in one piece. The guides c extenda short distance below the plate (1 and a sufficient distance above theplate to prevent the splash from the stamps coming out at the top, andare of a diameter sul'licient to permit the stampheads to work freelytherein. To prevent wear on the inner faces of the lower guides, theyare provided with bushings or linings of wrought-iron, steel, or othersuitable metal, and to protect the heads of the stamps from wear bycontact with said hard-metal lining they are ineased in close-fittingjackets f of wrought-iron or steel or other suitable metal. \Vhen thebushings or casing wear to any extent, they can be readily replaced byothers, and thus all wear is practically taken off the permanent orfixed parts of the apparatus. As the mortar is more rigid than theframe. and as these guides are carried by and in fact are parts of themortar, it follows that these guides are more substantial than guidescarried by the upright supports could possibly be. Again, the guidesbeing near the dies there is not so much strain or leverage against themwhen the stamps strike a glanc' ing blow,

As the principal work done by stamp-mills is wet-crushing, it is evidentthat the water can be carried into the mortar through the guides, thuswashing the sand down and effectually lubricating the contact-surfacesof the guides and stamps.

I have previously stated that some stampmills employ wooden guides andstated the objections to the use of such guides. Metal guides are alsoextensively used, and it is claimed that they are not so troublesome andexpensive to keep in repair. These metal guides are, however, made intwo parts similar to common shaft-boxes, the parts forming the guidesfor each stamp being separate from and independent of the other guides.As these sectional guides are secured to the cross-bars of the frame bymeans of bolts and nuts, it follows that it is necessary to remove thebolts and nuts before the bearings or guides can be removed.

By my construction of upper guides I dispense altogether with sectionalbearings and so construct the boxes that they can be removed from theframe and off the stem of the stamps without removing bolts or nuts.

Each hearing or guide II consists of a box having a cylindrical bore forthe stem of the stamp, with a dovetailed or T groove in its rear faceand with a top flange h, adapted to overlap and rest on the cross-beamI, which carries the entire series of upper bearings or guides.

1 represents the anchors or clamps rectangular in shape and preferablybeveled at their upper ends to enable them to-be readily and quicklyentered in the slots in the rear sides of the bearings. Each bearing isadapted to receive one clamp or anchor, and each clamp or anchor is heldin place by two bolts engaging same preferably near its upper and lowerends, the ends of the bolts being screwthreaded and enteringscrew-threaded holes in the anchor or clamp. Thus it will be seen thatby simply turning the bolts to lessen the pressure of the clampsoranchors against the shoulders h of the bearings, any or all of thebearings can be readily removed and lifted off the stem. These guides orbearings are lined with bushings of soft metal to prevent rapid wear ofthe stems. These bushings are preferably in the shape of tubes of properdiameter and length, and are held in place, preferably, by turning theend of the bushingover the upper and lower ends of the hearings orguides.

The stamps J consist, essentially, of a stem '11, head j, and shoe 7c,the stem carrying a tappet L, which is engaged byits cam on thecamshaft. As before stated, the head of the stamp is ineased in a hardmetal covering to protect it from wear. The head is also provided withtransverse slots on and a, the former crossing the bore 0 for the lowerend of the stem and the latter crossing orcommunicating with the borefor the shank of the shoe. The stem and shank of the shoe both projectslightly beyond the outer edges of their adjacent or respectivetransverse slots, so that a wedge or key passed into either slot willengage the end of the shank or stem, as the case may be. Thus it will beseen that by driving the wedge or key into the transverse slot the stemor shank can be forced out or so loosened as to permit of its readyremoval.

It is evident that slight changes might be made in the form andarrangement of parts herein shown without departing from the spirit andscope of my invention, and hence I would have it understood that I donot confine myself to the exact form and construction herein described;but,

Having fully described my invention ,what I claim as new, and desire tosecure by Letters Patent, is-- 1. In a stamp-mill, the combination, witha mortar and a cover therefor, the latter carrying a series ofcylindrical guides provided with removable hard metal linings, of aseries of stamps, the heads of which are provided with a hard metaljacket or covering, sub stantially as set forth.

2. In a stamp-mill, the combination, with a frame, a mortar, a series ofstamps, and means for elevating the latter, of a series of upper guides,each provided with a slotted rear face, an anchor-bar adapted to rest insaid slot, and -bolts securing the anchor-bars to the frame,substantially as set forth.

3. In a stamp-mill, the combination,with a frame and stamps, of a seriesof bearings, each of the latter having a dovetailed or T- shaped groovein its rear face, the said groove being open at the lower end, ananchor-bar adapted to enter said slot at the open end, and bolts forlocking the clamping-bar to the frame.

4. In a stamp-mill, the combination, with a frame and stamps, of aseries of upper bearlngs, each having a rearwardlyprojecting flange anda dovetailed or T-shaped groove open at its lower end, an anchor-baradapted tailed or T-shaped groove, and bolts carrying devices adapted toenter said groove and lock the bearing in place on the frame,substantially as set forth.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

JAMES M. MOFARLAND.

Witnesses:

F. P. LANGAN, E. U. MOOABE.

